 (defn volume-integrator
   [scene id]
   {:pre [(conf/volume-integrators id)]}
-  (append-singleton scene :volume-integrator (name id) {}))
+  (append-singleton scene :volume-integrator id {}))
 
 (defn renderer-slg
-  [scene {:keys [cpu? gpu? ]}]
+  [scene {:keys [cpu? gpu?]}]
   (append-singleton
    scene :renderer "slg"
    {:config

             (str (serialize-lxv scene* base-path)))
         lxs))))

(defn- append
  ([scene group id opts]
     (append scene group id opts false))
  ([scene group id opts singleton?]
     (-> (if singleton? (dissoc scene group) scene)
         (assoc-in [group id] (or opts {})))))

(defn- append*
  [scene group xs]

             :or {cone-angle 30 cone-delta 5 from [0 0 1] to [0 0 0]}
             :as opts}]
  (append
   scene :lights id
   (merge
    (light-common scene opts)
    {:__transform tx
     :__type :spot-light
     :from [:point-vec [from]]
     :to [:point-vec [to]]
     :coneangle [:float (->degrees cone-angle)]
